Absorption refrigerating apparatus



June 1945. N. ERLAND AF KLEEN 2,377,332

ABSORPTION REFRIGERATING APPARATUS Filed May 15, 1941 2 Sheets-Sheet 1 INV ENT OR. g JVi/w Erlmzzi a Klee/1 jmQ N. ERLAND AF KLEEN ABSORPTION REFRIGERATING APPARATUS Filed May 15, 1941 2 Sheets-Sheet 2 INVENT OR. 'lami qfK/ii jW/J 5/ M ATTORNEY fi atented E aine 5, 15

are sTArs 2,377,832 ABSORPTION anrmonna'rma APPARATUS Nils, Erland a! Klecn,

Stockholm, Sweden, as-

slgnor to Kleen Refrigerator, Ina, Hoboken, N. .L, a corporation Delaware Application May 15,

194i, Serial No. 393,599

unit or a plurality of intermittent units operating in alternate phase relation to one another. However, ior a plurality of boiler absorbers employed in a single intermittent unit, or in a plurality of intermittent units operating in the same phase relation to one another to maintain thenecessary amount of refrigerant in circulation, it isnot possible with the thermostat devices heretofore known. to accurately control the operation of such, unit or units. 7 I

It is therefore the primary object of the present invention to provide a thermostat control for a plurality of boiler absorbers, either of a single intermittent unit, or of separate intermittent units operating together as a group. 7

For example, in certain installations, a plurality of boiler absorbers in. a single intermittent unit or in separate intermittent units are adapted to be heated simultaneously and at the same 3 rate of heat input, or respectively diflerent amounts of heat are supplied simultaneously to a plurality of boiler absorbers but at a uniform-rate of input for all boiler absorbers, and it-is therefore another object of the present invention to provide a thermostat arrangement which not only controls the operation of a single intermittent unit. or a plurality of intermittent units from one phase to the other, but also regulates the heat input to the several boiler absorbers.

In other installations, each intermittent unit has a plurality of connected boiler absorbers adapted to be cooled by acommon cooling system. In such installations, the amount of heat required for 'one boiler absorber might not coincide with that required for another boiler absorber, or ii. the same amount is required for each boiler absorber, the heating of one might not coincide with that of another. However, inasmuch as a common cooling system is utilized for the plurality of boiler absorbers, it becomes necessary to shift the operation of the unit from the generating phaseto theabsorbing phase only when each boiler absorber has been supplied with the required amount or heat. It is therefore a further object of the invention to provide a thermostat arrangement for individually controlling the heat 30 accompanying drawings, and more input to a plurality of boiler absorbers in an absorption unit and for 'controllingthe operation of the unit Irom one phase-to the other;

In still other installations, a plurality of boiler absorbers in a single intermittent unit, or in separate intermittent units, are adapted to be heated simultaneously Y and require .the same amount of heat, but the heating. means employed might raise the temperature in one-boiler absorber more rapidly than in another and in order to prevent overheating of the same, and yet to.

maintain the predetermined temperaturesubstantially constant, it becomes necessary t0'in-.

termittently shut oi the supply of heat to one boiler absorber while ,the other continues to be heated. It is therefore still another object of the invention to provide a thermostat arrange- {ment to control'not only the operation from'one phase to the other of a single intermittentunlt go embodying a plurality of boiler absorbers, or of a plurality of intermittent units operatingin the same phase relation to one another, but ,also't'o intermittently control the heat input to some or the boiler absorbers.

With the above and other objects in view which will appear as the description proceeds, the-invention consists in the novel features hereinafter more fully set forth in the following'description, illustrated byway of example in-the particularly pointed out in the appended claims.

Referring to the drawings in which numerals of like character designate similar parts throughout the several views,

Fig. 1 is a diagrammatic view of one form of thermostat control in accordance with the present invention'for an intermittent absorption refrigerating installation embodying a plurality of boiler absorbers adapted to be heated'simultaneously and at the same rate oflieat input;

Fig. 2 is a similar view of a diiferent form of thermostat control in accordance with the invention for an intermittent type absorption refri crating installation embodying a plurality oi boiler absorbers in a single intermittent unit adapted to be cooled by a common secondary cooling system; i

Fig. 3 is a similar view of another form of thermostat control for an intermittenttype absorption refrigerating installation embodying a plurality of boiler absorbers adapted to be heated simultaneously, and requiring the same amount of heat, but wherein the heating means heats one boiler absorber more rapidly than another. and

Fig. 4 is a temperature chart illustrating the operation of the thermostat control of Fig; 3.

In the drawings, referring first to Fig. 1, two vessels or boiler-absorbers III and Illa are shown charged with suitable solid absorbent material II and Ila. respectively. The boiler-absorbers may form parts of separate intermittent type absorption refrigerating systems or units operating together on alternate generating and absorbing periods, or the two boiler-absorbers may form parts of a single intermittent type absorption refrigerating system or unit having alternate generating and absorbing periods. In either case,

the two boiler-absorbers Ill and Illa are heated simultaneously during the generating periods to drive out refrigerant vapors from the solid absorbent II and Ila into pipes I2 and l2a, respectively, to the condensing and evaporating parts of the refrigerating apparatus (not shown) The boiler absorbers are cooled simultaneously during the absorbing periods by any suitable means, such forexample as the cooling chambers I3 and I3a,- respectively, of'separate secondary cooling systems, or of a common secondary cooling system, through which system or systems a volatile medium is circulated in heat exchange relation with the boiler absorbers III and Illa to permit the re-absorption of the refrigerant by the absorbent.

For convenience, an electrical system is illus- 30 trated for heating the boiler absorbers and consists of elements Il and Ila arranged inside separate flues I5 and I5a provided centrally of the respective boiler absorbers Ill and Illa and adapted to be energized from a suitable source of'current. The circuit to the heating elements Il and Ila is controlled by a thermostat switch comprising pivoted lever I6 carrying a pair of contacts I1, I1a connected to the positive line of the source of current and adapted to cooperate with a pair of fixed contacts I8, I8a adjacent one side of the pivoted lever. A transverse rod I'S, movable in one direction by means of spring loading device 20, is operatively connected to the pivoted lever I6 to shift the latter on its pivot into circuit-making position, said rod being movable in the opposite direction, to shift the lever I8 into circuit-breaking position,' by a fluid pressure system 2| responsive to the temperature in boiler absorber I 0. A snap spring 22 cooperates with one end ofthe switch lever. I8 to yieldably maintain the latter in either one of its aforesaid operating positions.

The heating elements Il and Ila are adapted to-be energized at the same rate and for this purpose I provide an automatic regulating device comprising a lever 23 fulcrumed intermedil ate its ends as at 2l and carrying apair of contacts 25 and 25a longitudinally spaced from one current carrying and the latter similarly connected to heating element lla' by line 23a. Contact 25 is adapted to cooperate with a segment 21, connected at one end to contact I8 by current carrying line 23, and with a resistance coil 29 connected to the qopposite end of the segment 21. The second contact 25a on the lever 23 is adapted to cooperate another, the former electrically connected. by A line 26 to heating element Il its fulcrum in one direction, while a second fluid pressure system 30a responsive to the temperature in boiler absorber Illa cooperates with the opposite side of the lever to rock the same in o the opposite direction.

The segments 21, 21a and the reistance coils 29, 29a are oppositely disposed with respect to one another on each side of the lever 23 so that when the latter is rocked in one direction, for

H) example, clockwise, contact 25 will be .moved across resistance coil 29, while contact 25a will be moved across segment 21a. On the other hand, when lever 23 is rocked in a counterclockwise direction, contact 25 will be moved across 1:; segment 21, while contact 25a will be moved across resistance coil 29a.

The lever 23 is preferably spring loaded by means of a coil spring 3|, the loading pressure of whichis adjustable by a threaded nut 32 mov- 20 able along a transverse threaded bolt 33 rotatably supported at its opposite ends in a stationary yoke 3l,to counteract any differences between the fluid pressure systems 30 and 33a.

Having thus described one form of control device, its operation is as follows:

With pivoted switch lever I8 and fulcrumed lever 23 occupying the positions shown in Fig. l, the heating elements ll and Ila are both energized at the same maximum rates and will continue to be so energized as long as the amount of heat input or the rate of heat is the same to each' boiler absorber I0 and, Illa. When the predetermiried temperature is reached, the fluid pressure system 2I will shift the pivoted lever II to its circuit-braking position indicated by dot-anddash line I33, in .which position, the valve or valves (not shown) of the secondary cooling system or systems will be opened to permit the necessary cooling for the absorbing phase opera- 4 tion.

In the event the temperature rises more rapidly in one boiler absorber, for example in boiler absorber I0, than in the other boiler absorber Ila, or the heating element Il is energized at a faster rate than element Ila, fluid pressure system 33.

, will overcome the pressure in system 33a to wing fulcrumed lever 23 in a clockwise direction, movthe fluid pressure system 30a will gradually restore the lever 23 to its original position.

For a more rapid rise in boiler absorber Ila, or energization of element Ila. at a faster rate than element M, the fulcrumed lever ,23 willbe swung counterclockwise by fluid pressure system 33a tomaintain the same rate of energization of heating element Il through contact 2| and segment 21, but to reduce the rate of energization of 5 sistance coil 23a.

Thus, the thermostat arrangement in this form of the invention not only controls the operation of the unit or units from one phase to the other but also regulates the heat input to the plurality of boiler absorbers adapted to be heated simultaneously.

In Fig. 2 boiler absorbers II and Illa are connected together by conduit 36 to form a battery or series of combined generating'and absorbing elements in a single intermittent unit, MW

Heating element Ila through contact 250. and reca y n line 53.

to be heated by heating elements I 4 and Ma, re-

spectively, the refrigerant vapors generated dur-' ing such heating passing Irom boiler absorber It) to boiler absorber Illa and finally passing through conduit 86 to the condensing and evaporating parts of the primary system (not shown). The cooling jackets l3 and Ba of the boiler absorbers Ill and llla, respectively, are also connected together by pipe 31 so that both jackets form vaporizing vessels for a volatile medium circulating in a secondary cooling system. The vaporized medium passes through vapor pipe 38 leading from the jacket a to a double condenser 39 where the medium is condensed and is delivered to. a liquid collecting tank 40 from whence it'flows through pipe 4| to the cooling jacket i 3. A valve 42 interposed in the pipe 4| and operated by a thermostat device hereinafter described in detail, controls the circulation of volatile medium through the secondary system. The double condenser 39 is preferably arranged in an air duct 43 and a motor-driven fan 44 is employedin the bottom of the air duct to increase the air flow therethrough.

In the installation shown, the circuit to the heating elements i4 and a is controlled by a double thermostat arrangement comprising a pair of pivoted arms 45 and 45a carrying a circuit-making member 46 and 4611,, respectively, the former adapted to cooperate with a pair of contacts 41 and 48, and the latter adapted to cooperate with a similar pair of contacts 41a and 48a. Contacts 41 and 410. are connected to a suitable source of current while contacts 48 and 48a are electrically connected to the heating elements I4 and Ho, respectively. The arm 45 is adapted to be rocked on its pivot by a rod '49 operatively connected thereto intermediate its ends and normally urged in one direction by a spring loading device 50 to rock the arm 45 into circuit-making position with contacts 41 and 48,

said rod being movable in the opposite, direction against the loading device by a fluid pressure system i responsive to the temperature in boiler absorber Ill. Arm 45a is also adapted to be rocked on its pivot to make and break the circuit to the heating element I4a by a separate rod 49a normally urged in one direction by a spring loading device We, and in the o posite direction 'by fluid pressure 5m responsive-to the temperature in boiler absorber l to.

The valve 42 and themotor-driven fan 44 are I alsoadapted to be controlled'by the double thermostat arrangement and for this purpose, each pivoted arm 45 and 450 carries a contact member 52 and 52a, respectively, electrically insulated from circuit-making members 46 and 46a, re-

spectively, and connected together by current 5212 cooperate with complementary fixed contacts 54 and 540, respectively, the former electrically connected to the valve 42 and to the motor-driven fan 44, and-the latter connected to the. source of current. 3

It will thus be seen that in the event one boiler absorber requires less heat than the other but .each heating element supplies the same amount of heat, or if the boiler absorbers each require the I same amount of heat but one heating element supplies more heat than the other, or the heating of one boiler absorber does not coincide ex-' 20 or separate systems.

5 carrying lines 82 and 63, respectively.

In this installation, although both boiler ab- The cantact members 52 and ary cooling system is employed to cool both boiler absorbers, the valve 42 and Ian assembly 44 willnot be energized until both boiler absorbers have been heated to their respective end point teni- -5 peratures and the application of heat to both also controls the operation of the unit from one phase to the other.

In the installation shown in Fig. 3, the two boiler absorbers II and Ila employed either in a single unit, or inseparate'units, are adapted to be heated simultaneously by heating elements l4 and Ho, respectively, tor'the generation of refrigerant vapors, and cooled by the volatile mediumcirculating through the cooling jackets l3 and 13a of either a common secondary system As in the .case otthe installation heretofore described in connection with Fig. 1, the operation of the unit or uniw from one phase to the other is controlled by a single thermostat device comprising pivoted lever "5 i6, transverse operating rod IQ therefor movable in one direction by spring loading device 20, and in the opposite direction by a fluidpressure system 2| responsive to the temperature in boiler absorber J0. However, in this instance, pivoted 'lever It carries only one contact member 80 connectedto the source of current and adapted to cooperate in one position of the lever with a complementary contact 8| electrically connected to both heating elements l4 and 14a by current ,sorbers l0 and Illa requirethe same amount of heat,the' output of element l4a might be greater than that ofv element l4. Consequently, boiler absorber illa will be heated up to its predetermined temperature more rapidly than boiler ab-' sorber l0. Therefore, in order to prevent overheating of the boiler absorber "a and yet to v maintain the predetermined temperature sub- 4 stantially constant therein-until the boiler absorber It) has attained the aforesaid predetermined'temperature, there-is provided a thermostate switch 65 interposed in the line 63 nd responsive to the temperature in boiler absorber Ma to intermittently break the circuit to the element Ma. When the boiler absorber it reaches the predetermined temperature, lever is will be rocked by the fluid pressure system at to the posi-. tion indicated by dot-and-dash line E33 to shift the operation of the unit or units to the absorbing phase by permitting the circulation of a volatile medium through the cooling Jackets 83 and Wu.

The operation of the installation just described is clearly illustrated in Fig. 4 wherein t to designates the bottom temperature in the boiler absorbers l6 and Illa when the lever It .will be rocked to its circuit-closing position by the spring loading device 25 to energize heating elements l4 and Ma, and T designates the top temperature in- 65 the .boiler absorbers when'the lever i6 will be rocked to its oppositeposition by fluid pressure system ,2! to deenergize the heating elements'and openthe valve or valves of the secondary system or systems. During the generating hase, the

7 temperature rise in boiler absorber Ila will tollow line. 66 while that in boiler absorber, it will follow line 61, and when the predetermined temperature is reached in boiler absorber lfla, the thermostat 65 will operate'to open the circuit intermittently .to heating element l4a so that the temperature remains substantially constant as indicated by line on until boiler absorber la is heated by its heating element I4 to the predetermined temperature.

While I have shown and described the inven'- vention may be readily understand by thoseskilled in the art without further description, it being borne in mind that numerous changes may be madein the details thereof without departing from,the spirit of the invention as set out in the following claims.

What I claim and desire to secure by Letters Patent is:

1. In absorptionirefrigerating apparatus of the intermittent type, the combination with a plurality of boiler absorbers adapted to be heated conjointly to a predetermined temperature during the generating phase but .at respectively different rates; of a thermostat device responsive to the temperature in the boiler absorber being heated at the minimum rate, for controlling the operation of the apparatus from one phase to the other, and a separate thermostat device responsive to the temperature in the boiler absorber being heated at themaximum rate of heat input and operable at said predetermined temperature to intermittently control the heat input to said bination of heating means for each of said vessels, means acted upon by changes in conditions in each of-said vessels and cooperating with said heating means during operation 01' said vessels as generators to vary the heat input to one without affecting the heat input to another one of said vessels upon changes in conditions in one diflerent from those in the other one of said vessels,

and means acted upon by changes in conditions in one of said vessels and cooperating with said heating means during operation 01' said vessel as generator to terminate the heat supply to all of said vessels.

5. In absorption type refrigerating apparatus including a plurality of vessels operating alternately as generators and as absorbers; the combination of heating means for each of said vessels, and control mechanism including means ,acted upon by changes in conditions in each of said vessels and movable to one side of a median plane upon change in conditions in one of said vemels different from another one of said vessels to vary the rate of heat input to said second vessel and movable to the other side of the median plane upon change conditions in the secondnamed vessel different from said first vessel to vary the rate not heat input to the first-named vessel, and means acted upon by changes in conditions in one ofsaid vesselsand operative at a last named boiler absorber, to maintain said pre- .determined temperature substantially constant therein until said first named boiler abosrber is," heated to the aforesaid predetermined temperature.

2. Absorption type refrigerating apparatus including a plurality of vessels operating alternately as generators and as absorbers, heating means for each of said vessels, means responsive to the temperature in each of said vessels and coopcrating with said heating means during opera.- tion of said vessels as generators to vary the heat supply to one relative to the heat supply to another one of said vessels upon temperature rise in unediflerent from that in theother one of said first and second vessels, andmeans responsive to the temperature in one of said vesselsand opcrating at a predetermined temperature attained in said vessel during operation of the latter as generator to terminate the heat supply to all of said vessels.

3. Absorption type refrigerating. apparatus including a plurality of vessels adapted to act alternately as generators and as absorbers, heating means for each of, said vessels, and mechanism for automatically controlling the operation of said vessels as generators and as absorbers including means for varying the heat supply to one of said vessels relative to that to another one of said vessels upon temperature change in one different from that in the other one of said vessels during operation of said vessels as generators, and means for terminating the heat supply to all of said vessels in accordance with the conditions in only one of said vessels.

the heat sup to one relative to predetermined condition attained in said vessel during operation of the latter as generator to terminate the heat supply to all of said vessels.

6. Absorption type refrigerating apparatus including a plurality of vessels operating alternately as generators and as absorbers, heating means for each of said vessels, control mechanism including a pair of elements, means adapted to cooperate with one of saidelements to vary the heat supply to one without aflecting the heat supply toanother one of said vessels and adapted to cooperate with the other one of said elements to vary the heat supply to said second-named vessel without affecting the heat supply to said first-named vessel, and means responsive to the temperature in each or said vescluding a plurality of boiler-absorbers having alternate heating and cooling periods, heating means for said boiler-absorbers, cooling means for said boiler-absorbers, and control mechanism including means acted upon by changes in temperature in one of said boiler-absorbers for au tomatially controlling the heating and cooling periods of all of said boiler-absorbers, and means acted upon by changes in temperature in each of said boiler-absorbers and operating upon tem perature change in one diflerent from that in another one of said boiler-absorbers during each heating period of said boiler-abso'bcrs to vary the heat suppl to the other one of said first and second boiler-absorbers.

, '8. Absorption type refrigerating apparatus including a plurality of boiler-absorbers having alternate heating and cooling periods, heating means for each or said boiler-absorbers, cooling means common to all of said boiler-absorbers, control means for said cooling means including a valve, an energizing circuit for said valve including a plurality of switches in series, and a control device including a plurality or elements acted upon by temperature change in each of said boiierabsorbers, respectively, and each operating at a predetermined temperature to shut of! the heating means of the'respective-boiler-ab-g sorber and close one of said switches 9. Absorption type refrigerating apparatus including a plurality of boilereabsorbers having altermined temperature in said first boiler-absorberto shut oi! the heating means of said second boiler-absorber without afl'ecting operation or the heating means of said first boiler-absorber.

- 10. Absorption type refrigerating apparatus including a plurality of boiler-absorbers having alternate heating and cooling p riods, heating means for said boiler-absorbers, cooling means for said boiler-absorbers, and control for operating said heating means'and cooling constructed and arranged. to shut of! the heating me'ans of one of sai'dboiler-absorbers withoiit affecting operation of the heating means of another one of said boiler-absorbers and delay operation of the cooling means of said first boilerabsorber until termination of a heating period of said second boiler-absorber.

' 12. Absorption type refrigerating apparatus including a plurality of vessels operating alternately as generatorsand as absorbers, heating means for each of said vessels, and control mechanism for said heating means including means acted upon by changes in temperature in one of said vessels .and operating at a predetermined temperature attained in said vesselduring op eration of the latter as generator to interrupt the heat supply or all or said vessels, and means acted upon by changes in temperature in another one of said vessels and operating at a predetermined temperature attained in said vessel prior to the aforesaid predetermined temperature insaid first vessel to interrupt the heat supply to said second vessel without affecting the heat supply to said first vessel.

' 13.-Absorption refrigerating apparatu's'including two boiler-absorbers having alternate heating and cooling periods, heating means for said boiler-absorbers, cooling means for said boiler- .absorbers, and control means constructed and arranged to operate said heating means to heat each boiler-absorber to a predetermined end temperature and to prevent operation 01' said cooling means until both boiler-absorbers have means alternately including means acted pon by changes in temperature in one 01' said boiler-absorbers and operating at a predetermined temperature attained during each heating-period. of said. boiler-absorber to. initiate the cooling period or all or said boiler-absorbers, and means acted upon by changes in temperature in another one or said boiler-absorbers and operating at a predetermined temperature attained in said second boiler-absorber prior to the-aforesaid predeter-- mined temperature in said flrst'boiler-absorber to shut on the heating means of said'second boiler-absorber without affecting the heating means or said first boiler-absorber-and the cooling means or either ofsaid first and second-named boiler-absorbers. I a

11. Absorption type. refrigerating apparatusincluding .a plurality of boiler-absorbers having alternate heating and cooling periods, heating means tor each or said boiler-absorbers. cooling means for each or said boiler-absorbers, and meansi'or alternately cooling means of each of been heated to their respective predetermined endtemperatures.

p 14. Absorption refrigerating apparatus includ ing a pair or boiler absorbers, heating means for each boiler absorber, and control mechanism including thermostatic means responsive to the Y (temperature of each or said boiler absorbers in control or said heating means, said control mechanism being constructed and arranged to initiate application ofheat to both of said boiler absorbers simultaneously and to regulate said heating ing means to heat said boiler absorbers to predetermined end temperatures. l5. Absorption refrigerating apparatus including a pair of boiler absorbers, heating means for each boiler absorber, and control mechanism for saidheatinsmeans constructedandarrangedto initiate application of heat to both of said boiler absorbers simultanoously including thermostatic ineans responsive to a thermal condition induced asa consequence orptheoperation orsaidheating means to regulate the operation said heating to heat said boiler absorbers to predeter-. minedendtempcratures. 

